Multi-Tech Systems MT5634SMI V.92 ユーザーズマニュアル

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Chapter 3 – Fax Class 2 Commands 
Multi-Tech Systems, Inc. SocketModem MT5634SMIxx Reference Guide (S000263C) 
 
84    
Receive Quality Thresholds  
Class 2.1 
+FRQ 
Write syntax: 
+FRQ=<pgl>,<cbl>  
 
Values: 
0 to 64h for <pgl
0 to FFh for <cbl
Default: 0,0 
This compound parameter replaces the +BADMUL and +FBADLIN parameters used 
in Class 2. The modem may use it to make the "Copy Quality OK" decision in the 
T.30 flow chart (Figure A.7/T.30). If it is used, the modem shall judge copy quality 
unacceptable if either the percentage of good lines is too low or too many 
consecutive lines contain errors. Bad line counts are reported in the +FPS:<blc
response. A value of 0 disables either subparameter for use in copy quality checking. 
The first subparameter, <pgl>, specifies the percentage of good lines (e.g. with 
negotiated number of pixels) required for a page to be considered acceptable. For 
example, if the modem counted bad lines (as reported in the +FPS <blc
subparameter) and total line count (as reported in the +FPS<lc> subparameter); the 
percentage of good lines would be computed by the following equation: 
100 × (<lc> – <blc>) / <lc>   
If the resulting value is less than the value in <pgl>, the page is unacceptable. 
The second subparameter, <cbl>, specifies the maximum tolerable number of 
consecutive bad lines. If this value is exceeded for a given page, the modem shall 
consider the page unacceptable. 
If the page is found unacceptable by either criteria, the modem shall report the value 
2 for the +FPS <ppr> subparameter, and store that value into the +FPS parameter. 
Class 2 
+FBADMUL 
Write syntax: 
+FBADMUL=<value
Values: 0–255 
Default: 20 
This is one of two Class 2 parameters used to determine “Copy Quality OK” on the 
T.30 flow chart. The number of lines received with a bad pixel count is multiplied by 
this number. If the result exceeds the number of lines in the page, then the error rate 
is too high. A value of 20 corresponds to a 5% error rate. 
A value of 0 implies that error checking is not present or is disabled. 
Class 2 
+FBADLIN 
Write syntax: 
+FBADLIN=<value>  
Valid values: 
0–255 
Default value:  10 
This is the other Class 2 parameter used to determine “Copy Quality OK.” If the 
number of consecutive lines in normal resolution (98 dpi) mode that have pixel count 
errors is equal to or greater than <value>, then the copy quality is unacceptable. If 
the number of consecutive lines in fine resolution (196 dpi) mode that have pixel 
count errors is equal to or greater than <value> × 2, then the copy quality is 
unacceptable. “Copy Quality Not OK” occurs if either the error percentage is too high 
or if too many consecutive lines contain errors. Bad line counts are reported in the 
+FPTS: response. 
A value of 0 implies that error checking is not present or disabled.